This invention relates generally to systems for aerial refueling operations between a tanker aircraft and a receiver aircraft.
More specifically, this invention relates to a system on the tanker aircraft for improved visibility of the receiver aircraft by the operator of the refueling station within the tanker aircraft during night aerial refueling maneuvers both to visually acquire the receiver aircraft and to engage the fuel line boom of the tanker with the receptacle located on the receiver aircraft.
Conventional methods for performing aerial refueling operations between a tanker aircraft and a receiver aircraft involve the use of a fuel line in the form of a boom extending downwardly and rearwardly from the tanker, means positioned on the boom, controllable from within the tanker, for maneuvering the boom into a position appropriate for coupling with a receiver aircraft, and a coupler at the end of the refueling boom for interconnection with a fuel receptacle on the receiver aircraft.
A receiver aircraft, prior to establishing a suitable position for receiving fuel from the tanker, must first locate the tanker by such means as radar or homing devices as are known in the art. Once the tanker is located, the receiver aircraft then must assume and maintain a position immediately behind and below the tanker within the so-called "refueling envelope", which is defined as that volume of space behind the tanker the allowable limits within which the refueling boom may be maneuvered horizontally and vertically and extended or retracted without imposing undesirable stress on the refueling boom. The receiver aircraft ordinarily must rely on visual contact with the tanker from a point several hundred yards (depending on lighting and weather conditions) from the tanker to the proper position within the refueling envelope. Of particular importance and difficulty are the delicate maneuvers, and the attendant careful coordination between boom operator and receiver aircraft pilot, required at the precise point of hookup and in maintaining the appropriate relative positions of tanker and receiver aircraft during refueling. This operation, although requiring a high degree of skill by the boom operator and receiver aircraft pilot, is relatively routine during daylight and favorable weather conditions, but with existing methods, aerial refueling operations performed at night or under other limited visibility conditions, is extremely difficult and hazardous.
Methods heretofore proposed and/or used for properly positioning a receiver aircraft behind a tanker for refueling at night, and for maintaining that position, include the use of a guidance light display mounted on the aft belly of the tanker aircraft in view of the receiver aircraft to relay to the receiver aircraft pilot information describing his speed and position relative to the tanker and instructions to adjust that speed and position, such as that described in U.S. Pat. No. 4,158,885 to Neuberger. Other proposed methods involve the use of optical or radiation transmitting and sensing devices located in the tanker and receiver aircraft or on the refueling boom for providing relative speed and position information displayed on monitors to the boom operator and receiver aircraft pilot, such as that described in U.S. Pat. No. 3,285,544 to Chope, et al. Still another method involves the use of a bright visible incandescent light mounted on the tail of the tanker to enable the receiver aircraft to locate the tanker and to assume its specific refueling position, and to illuminate the receiver aircraft to the boom operator stationed in the tanker enabling him to maneuver the refueling boom into position for connection with the receiver aircraft.
Inherent in the use of the foregoing described methods for aerial refueling at night or under other limited visibility conditions are certain difficulties severely limiting the usefulness of those methods. First, and most prominently and unavoidably, both the tanker and receiver aircraft are subject to radar detection, and, therefore, any covert aerial refueling operation must be performed with dispatch. Second, the use of homing devices in the tanker and voice communications between tanker and receiver aircraft further compound the problem of detection of the tanker. Third, the use of guidance light displays disclose with accuracy the location of the tanker and, fourth, the use of a bright visible wavelength light on the tanker to illuminate the receiver aircraft discloses the position of both the tanker and the receiver aircraft. Contributing to the foregoing problems, especially as applied to nighttime aerial refueling operations, is that certain aircraft, particularly fighter aircraft, by design and/or camouflage, are difficult to discern to a boom operator stationed in a tanker, and further, conventional lighting on the tail of the tanker and within the refueling station within the tanker, produce glare on the canopy of a receiver aircraft, further impairing the vision of the pilot of the receiver aircraft.
The foregoing problems inherent in aerial refueling operations, particularly as associated with operations at night or under other limited visibility conditions, have been eliminated or significantly lessened in critical importance by the invention described herein, providing a refueling station for a tanker aircraft uniquely provided with means for illuminating a receiver aircraft with infrared light and means enabling the pilot of the receiver aircraft to view the tanker aircraft without interference from glare so as to safely, quickly and accurately maneuver the receiver aircraft into position for interconnection with the boom, with minimum communication between tanker and receiver aircraft. The invention described herein may also be used in conjunction with existing aerial refueling methods to improve the overall performance and efficiency of aerial refueling operations.
Accordingly, it is an object of this invention to provide an improved aerial refueling system.
It is a further object of this invention to provide an improved aerial refueling system for performing refueling operations at night or under other limited visibility conditions.
It is still another object of this invention to provide an improved aerial refueling system for covert nighttime refueling operations.
These and other objects of the invention will become apparent as the description thereof proceeds.